Social media marketing is all the rage, but is it efficient? John Dvorak argues that social media may work well for artists and small businesses, but he’s not so sure it’s a great investment for larger companies. He estimates, based on personal experience, that a typical social media pitch has a 0.4% success rate, roughly a quarter of direct mail. How does that square with what you’ve experienced? Check out this and other thought-provoking links that didn’t quite make the daily SmartBrief on Social Media e-mail.